The present invention relates to the making of compound powder and more particularly the invention relates to the manufacture of a compound powder or powder of a compositional material which includes a noble metal on one hand and a non-noble metal oxide on the other hand, under utilization of a watery (watery based) solution which includes salts of these metals and is atomized in a hot reactor.
German patent 29 29 630 discloses a method for the manufacture of a silver based powder, having in particular a composition of Ag and CdO. The powder is to be used for making electrical contacts. The powder itself is made by spraying (atomizing) a watery solution of silver salt and cadmium salt in a hot reactor, and the resulting powder particles, after the reaction has completed are separated from the hot gas in which they float, by means of a centrifugal precipitator which causes the separated metal particles to be collected. This particular approach is disadvantaged by the fact that the noble metal even for relatively low percentages in the non-noble metal oxide has the tendency to form a rather firmly adhesive coating, on the wall of the centrifuge resulting from the high relative speed between the powder particles and that wall.